JP3616533B2 - Initial connection system and control circuit thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an initial connection system and its control circuit, and more particularly to an initial connection system of a multistage relay system. More specifically, in the present invention, one master station and a plurality of slave stations are connected via a plurality of relay stations using a TDMA signal and a TDM signal (both time division multiplexing; time division multiplexing signals). In particular, the relay station and the slave station determine the initial connection timing for the upper station by the relay stage number signal (information) in the control channel transmitted from the upper station to the lower station. The present invention relates to an initial connection system and a relay station control circuit in a multistage relay system that performs initial connection.
[0002]
[Prior art]
For example, as shown in FIG. 3, in a TDMA wireless communication system having a star network configuration, a large number of slave stations 2 in a region are connected to a master station 1 via a large number of relay stations 3 installed in the same region. ing. The initial connection (acquisition) in the TDMA wireless communication system as shown in FIG. 3 is a function necessary for determining the transmission timing after the reception synchronization is determined, and is executed when the system is turned on. Various methods have been proposed for this initial connection.
[0003]
For example, in Japanese Patent Laid-Open No. 58-99044, a transmission timing of a burst signal for initial connection input to the slave station side by estimating the distance between the master station (control station) and the slave station (controlled station) in advance. A method for determining the value has been proposed. That is, an initial connection burst signal having a short time is inserted and transmitted in the initial connection time slot, and the position error of the initial connection burst signal in the initial connection time slot is detected by the master station. Further, high power level acquisition is used by a feedback loop method in which the position error information is notified to the slave station side and transmission timing control is performed on the slave station side. This proposal aims to prevent the time slot adjacent to the time slot for initial connection from interfering with or interfering with the time slot for initial connection by transmitting a short burst for initial connection.
[0004]
Also, for example, in Japanese Patent Laid-Open No. 2-4032, a method for determining the transmission timing by succeeding in the initial connection between the master station and the relay station based on the proposal described in Japanese Patent Laid-Open No. 58-99044 described above. Has been proposed. That is, the distance between the master station and the slave station is estimated in advance, and the transmission timing of the initial connection burst signal input to the slave station is determined. In addition, an initial connection burst signal is inserted into the initial connection time slot and transmitted.
[0005]
Furthermore, the relay station detects the position of the initial connection burst signal in the initial connection time slot, and inserts it in the initial connection time slot for the master station at a time position equal to the detection position of the initial connection burst from the slave station. To send. The master station detects the position error of the initial connection burst signal from the slave station in the initial connection time slot, notifies the slave station side of the position error information, and controls the transmission timing on the slave station side. That is, FIG. 4 shows the timing relationship when the system is simplified and the master station 1 is connected directly to the slave station 2 (not via the relay station 3).
[0006]
4, in the master station 1, and transmits c to the slave station 2 provided with a burst b for initial connection immediately after the transmission timing s downlink master station transmits c to the parent station 1 slave station 2. The signal (burst for initial connection) transmitted from the master station 1 is received by the slave station 2 after being delayed (transmission time) A by the distance between the master station 1 and the slave station 2, and received by the slave station 2. Timing is determined. The transmission f timing of the slave station 2 is determined by estimating the distance between the master station 1 and the slave station 2 on the slave station 2 side, calculating the offset amount B corresponding to this, and determining the transmission timing. A signal transmitted at the determined transmission f timing of the slave station 2 is delayed by the distance between the slave station 2 and the master station 1 and received by the master station 1.
[0007]
In general, if the slave station 2 can transmit data so that the master station 1 can wait for the reception timing, the (initial) connection is completed. That is, if the distance between the master station 1 and the slave station 2 is correctly input in the slave station 2, it is possible to accurately transmit (set) the reception timing to which the master station 1 is waiting. If the slave station 2 incorrectly inputs the offset amount B between the master station 1 and the slave station 2, an error D occurs as shown in FIG. 5, and the (initial) connection is not completed. In FIG. 5, the error D is shown as positive, but it may be negative. This error (amount) D is notified from the master station 1 to the slave station 2 as position error information, and the slave station 2 controls the offset amount B (transmission timing control).
[0008]
As shown in FIG. 6, when, for example, three-stage relay stations 3-ac are present between the master station 1 and the slave station 2, the downlink transmission g of the master station 1 is transmitted to the relay stations 3-ac. Then, after being relayed (receive / transmit) i, k, m, it is received by the slave station 2 and received. The slave station 2 estimates the distance between the master station 1 and the slave station 2 and performs uplink transmission q. The uplink signal transmitted q from the slave station 2 is relayed (received / transmitted) o, l, j by the relay stations 3-ac, and then received by the master station 1. As shown in the drawing, in order for the transmission g timing and the reception h timing of the master station 1 to coincide (completion of initial connection), it is necessary to grasp the distance to the master station 1 with high accuracy on the slave station 2 side. Become.
[0009]
In general, in the case of multistage relay, as shown in FIG. 7, the error in estimating the distance between the master station 1 and the slave station 2 in the slave station 2 increases as the number of relay stages increases and the distance increases. That is, even if the error is the same 10%, it is 1 km for 10 km, but 10 km for 100 km. Therefore, as shown in FIG. 8, when the distance estimation accuracy cannot be maintained sufficiently, it is necessary to take a wide initial connection (burst) time slot, but it interferes with signals from other adjacent (child) stations. there is a possibility.
[0010]
[Problems to be solved by the invention]
In the initial connection method described in Japanese Patent Laid-Open Nos. 58-99044 and 2-4032, the distance between the master station (control station) and the slave station (controlled station) is estimated in advance and input to the slave station side. There is a problem that the transmission timing needs to be set. That is, even when the number of relay stages is large, the master station (control station) or slave station must grasp the distance to the slave station (controlled station) or master station at the farthest point. The distance between the master station and the slave station is estimated in advance and input to the slave station. However, the accuracy of the distance input to the slave station is inserted in the initial connection time slot on the slave station side. Therefore, there is a problem that it is necessary to be within the time width of the initial connection time slot.
[0011]
That is, even when the number of relay stages is large, if the distance accuracy to the master station at the farthest point cannot be maintained, there is a possibility of interfering with or interfering with a time slot adjacent to the initial connection time slot. On the other hand, when the number of relay stages is large, if it is intended to ensure the distance accuracy to the master station at the farthest point, the time width of the initial connection time slot needs to be increased as the number of relay stages increases. .
[0012]
Furthermore, the master station has a problem in that the position error of the initial connection burst signal in the initial connection time slot is detected, the position error information is notified to the slave station, and the transmission timing is controlled on the slave station side. That is, since the burst signal for initial connection from all the slave stations reaches the master station, the number of participating stations increases as the number of relay stages increases, but the burst signal for initial connection is transmitted by only one station as a whole. Therefore, the use efficiency of the time slot for initial connection is remarkably lowered, and it takes time for all the stations to start up.
[0013]
Furthermore, the master station detects the position error of the initial connection burst signal from the slave station in the initial connection time slot, notifies the slave station side of the position error information, and controls the transmission timing on the slave station side. There's a problem. That is, as the number of relay stages increases, the number of participating stations increases, and the load of slave station control in the parent station increases.
[0014]
An object of the present invention is to provide an efficient initial connection system of a multistage relay system and a control circuit thereof.
[0015]
[Means for Solving the Problems]
An initial connection system according to the present invention is an initial connection system of a wireless communication multistage relay system using a time division multiplexed signal in which one master station and a plurality of slave stations are connected via a plurality of relay stations, Initial connection signal transmitting means for transmitting a burst signal for downlink initial connection to the master station, relay stage number information transmitting means for transmitting relay stage number information, and receiving an initial connection burst signal from the slave station for initial connection An initial connection means for completing the transmission, and a downlink relay means for relaying, to the relay station, the burst signal for downlink initial connection from the upper master station or the relay station to the lower slave station or the relay station; Upstream relay means for relaying an upstream initial connection burst signal from the lower slave station or the relay station to the upper master station or the relay station, and the upper master station or the relay station An addition relay means for adding 1 to the relay stage number information from a relay station and relaying it to the lower slave station or the relay station, and receiving the burst initial connection burst signal at the slave station Signal receiving means; relay stage number information receiving means for receiving the relay stage number information; distance estimating means for estimating a distance to the relay station immediately above; and the received relay stage number information and the estimated relay directly above And an initial connection signal sending back means for sending out the upstream initial connection burst signal at a timing based on the distance to the station, and providing the upstream relay station with the relay stage number information and the uplink from the slave station. a signal for controlling the estimated value of the distance estimation unit based on the reception timing of the initial connection burst signals provided the estimated value control means for sending to said slave station, further to the relay station, a straight upper Characterized in that a transmission timing adjusting means for adjusting a constant value round trip signal transmission delay time between the master station or the relay station.
[0016]
Further, the relay station is provided with transmission timing adjustment means for adjusting a round-trip signal transmission delay time between the master station or the relay station directly above it to a constant value. Further, the initial connection signal sending back means multiplies the round-trip signal transmission delay time adjusted to the constant value by the number of relay stages included in the relay stage number information, and the distance between the slave station and the immediately higher relay station The uplink initial connection burst signal is transmitted at a timing obtained by subtracting the time obtained by adding the round-trip signal transmission delay time corresponding to the transmission period of the downlink initial connection burst signal of the master station.
[0017]
The control circuit according to the present invention includes the master station and the relay of the initial connection system of the wireless communication multistage relay system using time division multiplexed signals in which one master station and a plurality of slave stations are connected via a plurality of relay stations. A control circuit included in a station and a slave station, the relay stage number detecting means for detecting the relay stage number information in the received signal from the host apparatus, and adding 1 to the relay stage number information from the host apparatus to the lower apparatus Relay stage number information adding means to be transmitted, burst detecting means for detecting an initial connection burst signal in the received signal from the lower apparatus, and for initial connection from the lower apparatus based on the relay stage number information from the upper apparatus transmitting data to adjust the burst transmission means which adjusts the transmission timing of the burst signal sent to the host system, the round trip signal transmission delay time between the master station or the relay station straight upper constant value Characterized in that it comprises a timing adjusting unit.
[0018]
The operation of the present invention is as follows. From the upper station (master station and relay station) to the lower station (relay station and slave station), the lower station side determines only the distance from the own station to the upper station by the relay stage number signal in the control channel transmitted. To determine the initial connection timing and perform the initial connection. As a result, it is only necessary to grasp the distance to the immediate upper station without grasping the distance to the master station at the farthest point. Further, since the distance accuracy is not so required, the possibility of interference and interference with the time slot adjacent to the initial connection time slot is reduced, and the width of the initial connection time slot does not need to be particularly wide.
[0019]
In the relay station, if the initial connection with the upper station in the relay station is established by controlling the initial connection only with the lower station by the burst signal monitoring circuit for initial connection, the initial connection from the lower station There is no need to relay burst signals. Therefore, even when multistage relay is performed, the use efficiency of the time slot for initial connection is increased, and further, the load of slave station control in the master station can be reduced.
[0020]
Each of the relay station and the slave station uses the relay stage number separation means for separating the signal indicating the number of relay stages included in the control channel received from the upper station, and the relay stage number information separated by the relay stage number separation circuit. Transmission timing adjustment circuit means for determining the transmission timing in the initial connection to the upper station. A relay stage number adding circuit for generating a signal obtained by adding +1 to the relay stage number information separated by the relay stage number separating circuit; and a multiplexing circuit for multiplexing the relay stage number information output from the relay stage number adding circuit on the received control channel. . Furthermore, an initial connection burst signal detection circuit for detecting the position of the initial connection burst signal from the lower station and a multiplexing circuit for multiplexing the detected position error information are provided.
[0021]
By using the relay stage number signal (information) in the control channel transmitted from the upper station (parent station and relay station) to the lower station (relay station and slave station), the distance between the upper station and the lower station Is input to the lower station side to determine the initial connection timing. As a result, it is only necessary to grasp the distance to the immediately higher station without grasping the distance to the parent station at the farthest point by performing the initial connection. Further, since the distance accuracy is not so much required, the possibility of interference and interference with the time slot adjacent to the initial connection time slot is reduced, and the width of the initial connection time slot need not be wide.
[0022]
In the relay station, it is not necessary to relay the initial connection burst signal by the initial connection burst signal monitoring circuit. Therefore, even when multi-stage relay is performed, the use efficiency of the initial connection time slot is increased, and The load of slave station control in the station can also be reduced.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an embodiment of a control circuit of a relay station in an initial connection system of a multistage relay system according to the present invention, and the same parts as those in FIGS. The control circuit according to the present invention is mainly composed of a circuit for initial connection existing in the relay station 3 in the multistage relay system shown in FIG. In FIG. 1, a relay station 3 to which the present invention relates is shown as (from a higher-order station constituting a downlink relay route from a higher-order station (master station 1 or relay station 3) to a lower-order station (relay station 3 or slave station 2) ( An antenna 11 and a receiver 12 for receiving a radio wave signal.
[0024]
It also has a demodulator 13 that demodulates the received signal, a multiplexing circuit 14 that synthesizes (multiplexes) signals to lower stations, a modulator 15 that modulates the transmission signal, a transmitter 16 that amplifies and transmits power, and an antenna 17. . Further, an antenna 26 for receiving a (radio wave) signal from a lower station constituting an upstream relay route from a lower station (child station 2 or relay station 3) to an upper station (relay station 3 or parent station 1) and reception Machine 25. Furthermore, it has a demodulator 24 that demodulates a received signal, a modulator 23 that modulates a signal to a higher-level station into a transmission signal, a transmitter 22 that amplifies and transmits power, and an antenna 21.
[0025]
In addition, a relay stage number separation circuit 18 that separates the relay stage number information from the control channel of the output of the demodulator 13 and a relay stage number + 1 circuit 19 that adds +1 to the relay stage number information and outputs the result to the multiplexing circuit 14 are provided. Further, it has an initial connection burst signal detection circuit 27 that detects a position error of the burst signal for initial connection from the lower station and outputs error information to the multiplexing circuit 14. Furthermore, a transmission timing adjustment circuit 28 is provided which inputs the relay stage number information separated from the relay stage number separation circuit 18 to the initial connection burst signal transmission circuit 29 as a timing when the local station makes an initial connection. In addition, it has an initial connection burst signal transmission circuit 29 for outputting an initial connection burst signal to the upper station.
[0026]
The operation of the embodiment of the present invention will be described with reference to FIG. In FIG. 1, the routes of the antenna 11, the receiver 12, the demodulator 13, the multiplexing circuit 14, the modulator 15, the transmitter 16, and the antenna 17 are routed from the upper station (master station 1 or relay station 3) to the lower station (relay station). 3 or a downstream relay route to the slave station 2). The output of the demodulator 13 of the downstream relay route is connected to the relay stage number separation circuit 18, separates the relay stage number information from the control channel, and outputs it to the relay stage number + 1 circuit 19 and the transmission timing adjustment circuit 28.
[0027]
The relay stage number + 1 circuit 19 adds +1 to the relay stage number information and outputs the result to the multiplexing circuit 14. The multiplexing circuit 14 multiplexes the information on the number of relay stages on the control channel. Accordingly, the relay stage number information is incremented every time the relay is increased by one stage. The antenna 26, the receiver 25, the demodulator 24, the modulator 23, the transmitter 22, and the antenna 21 are connected from the lower station (the slave station 2 or the relay station 3) to the upper station (the relay station 3 or the master station 1). It is an upstream relay route. The output of the demodulator 24 of the upstream relay route is connected to the initial connection burst signal detection circuit 27, detects the position error of the initial connection burst signal from the lower station, and outputs error information to the multiplexing circuit 14. The multiplexing circuit 14 multiplexes on the control channel.
[0028]
The relay stage number information separated from the relay stage number separation circuit 18 is input to the transmission timing adjustment circuit 28, and is used by the burst signal transmission circuit 29 for initial connection as a timing when the local station makes an initial connection, for initial connection. Outputs a burst signal. Accordingly, the master station 1 does not control the initial connection to all the slave stations 2, but the lower stations (slave station 2 or relay station 3) to which the respective higher stations (relay station 3 or master station 1) are directly connected. ) To control the initial connection. That is, the upper station is an initially connected control station and the lower station is a controlled station.
[0029]
As shown in FIG. 2, for example, when the master station 1 is connected to the slave station 2 via the relay stations 3-a to c, the downlink transmission g of the master station 1 is transmitted from the relay stations 3-ac to c. After being relayed (transmitted / received) i, k, m, it is received and received by the slave station 2. Delays E, F, and G due to relay are adjusted to be a constant value (maximum delay amount of one relay) regardless of the distance. That is, when the distance is short and the delay amount is small, a delay circuit is inserted to adjust the total delay amount to a constant value. Therefore, E = F = G = K (constant value), and the same applies to the downstream and upstream signals.
[0030]
However, here, for the convenience of explanation, the transmission delay amount (time) is constant for each of the downlink and uplink signals. However, in actuality, the total transmission delay time of the round trip (downlink and uplink) of the signal is a constant value. I just need it.
[0031]
The slave station 2 estimates the distance between the master station 1 and the slave station 2 and performs uplink transmission q. However, if the number of relay stages is three as shown in the figure, the delay amount generated by the relay is 2 (round trip) × 3 Since the number of relay stages is K (a constant value; known), the slave station 2 only needs to estimate the delay amount H corresponding to the distance to the immediately higher relay station 3-c.
[0032]
Since the distance to the immediately higher relay station 3-c is relatively short, it is not necessary to grasp the distance with high accuracy. The position error of the burst signal for initial connection is detected in the relay station 3-c immediately above, and if there is a position error, the slave station 2 is notified, and the slave station 2 performs transmission timing control according to the instruction of the relay station 3-c. Do. The uplink signal transmitted q from the slave station 2 is relayed (received / transmitted) o, l, j by the relay stations 3-ac, and then received by the master station 1.
[0033]
【The invention's effect】
As described above, according to the present invention, there is an effect that it is sufficient to grasp the distance to the immediately higher station without being aware of the distance to the parent station at the farthest point. That is, by using the relay stage number signal (information) in the control channel transmitted from the upper station (master station and relay station) to the lower station (relay station and slave station) No need to be aware of the station.
[0034]
In addition, the possibility of interfering with or interfering with a time slot adjacent to the initial connection time slot is reduced, and there is an effect that it is not necessary to increase the width of the initial connection time slot. That is, the distance (accuracy) between the control station and the controlled station is the shortest. Further, even when multi-stage relay is performed, the use efficiency of the initial connection time slot is increased, and there is an effect that the load of controlling the slave station in the master station can be reduced. That is, by providing the initial connection burst signal detection (monitoring) circuit in the relay station, it is not necessary to relay the initial connection burst.
[Brief description of the drawings]
FIG. 1 is a block diagram of an embodiment of the present invention.
FIG. 2 is a timing diagram of an embodiment of the present invention.
FIG. 3 is an explanatory diagram of a multistage relay system related to the present invention.
FIG. 4 is a basic timing chart of initial connection.
FIG. 5 is a basic timing chart of initial connection.
FIG. 6 is an initial connection timing diagram in the case of multi-stage relay.
FIG. 7 is an initial connection timing chart in the case of multi-stage relay.
FIG. 8 is an initial connection timing chart in the case of multistage relay.
[Explanation of symbols]
11, 17, 21, 26 Antenna 12, 25 Receiver 13, 24 Demodulator 14 Multiplexer 15, 23 Modulator 16, 22 Transmitter 18 Relay stage number separation circuit 19 Relay stage number + 1 circuit 27 Burst signal detection circuit 28 for initial connection Transmission timing adjustment circuit 29 Burst signal transmission circuit for initial connection

Claims (4)

An initial connection system of a wireless communication multistage relay system using a time division multiplexed signal in which one master station and a plurality of slave stations are connected via a plurality of relay stations,
An initial connection signal sending means for sending a burst signal for downlink initial connection to the master station, a relay stage number information sending means for sending relay stage number information, and receiving an initial burst signal for uplink initial connection from the slave station Providing an initial connection means for completing the connection;
The relay station has downlink relay means for relaying the burst signal for initial downlink connection from the upper master station or the relay station to the lower slave station or the relay station; and the lower slave station or the relay station Uplink relay means for relaying an uplink initial connection burst signal from the upper master station or the relay station, and adding 1 to the relay stage number information from the upper master station or the relay station, An adding relay means for relaying to the slave station or the relay station;
Distance estimation for estimating the distance to the slave station, the initial connection signal receiving means for receiving the burst signal for downlink initial connection, the relay stage number information receiving means for receiving the relay stage number information, and the relay station immediately above Means, and an initial connection signal sending means for sending the uplink initial connection burst signal with timing determined based on the received relay stage number information and the estimated distance to the immediately higher relay station,
Estimation to send a signal for controlling the estimated value of the distance estimation means to the slave station based on the relay stage number information and the reception timing of the burst signal for uplink initial connection from the slave station to the relay station immediately above A value control means ,
The initial connection system according to claim 1, further comprising transmission timing adjusting means for adjusting a round trip signal transmission delay time between the relay station and the parent station or the relay station directly above to a constant value. The initial connection signal return means multiplies the round trip signal transmission delay time adjusted to the constant value by the number of relay stages included in the relay stage number information, and corresponds to the distance between the slave station and the relay station immediately above the time obtained by adding the round trip signal transmission delay time, according to claim 1, wherein the sending the burst signal for the uplink initial connection at a timing obtained by subtracting from the transmission cycle of the downlink initial connection burst signal of the master station Initial connection system. 3. The initial connection system according to claim 1, wherein the time division multiplexed signal is a TDMA signal or a TDM signal. Included in the parent station, relay station, and slave station of the initial connection system of a wireless communication multistage relay system that uses a time division multiplexed signal in which one master station and a plurality of slave stations are connected via a plurality of relay stations A relay stage number detecting means for detecting the relay stage number information in the received signal from the host apparatus, and a relay stage number information adding means for adding 1 to the relay stage number information from the host apparatus and sending it to the lower apparatus. And burst detection means for detecting a burst signal for initial connection in a received signal from the subordinate apparatus, and adjusting the transmission timing of the burst signal for initial connection from the subordinate apparatus based on the relay stage number information from the superordinate apparatus Burst sending means for sending to the host device ,
And a transmission timing adjusting means for adjusting a round-trip signal transmission delay time between the master station and the relay station directly above to a constant value .

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